I have an self harm scar that still hasn't completely healed, gone away, or improved. What can I do? (Photo)

This was a one time occurance, so I've never dealt with a scar like this before. It's been a full year and it still itches and hurts sometimes. It's raised, and goes from light pink to a full red color sometimes. I tried a baking soda and vitamin E oil mix that someone online recommended for self harm scars, it didn't help at all. I also tried just vitamin E oil, as well as a scar cream for the full period it said to. The scar hasn't even improved in appearance. What can I do?